1. Field of the Invention
The present invention relates to a chip-component structure including a multilayer capacitor and an interposer to be mounted on a circuit board including the capacitor disposed thereon.
2. Description of the Related Art
Currently, chip components, especially, small multilayer capacitors are frequently used in circuit boards of mobile terminals such as mobile telephones. A typical multilayer capacitor includes a laminated body shaped like a substantially rectangular parallelepiped in which internal electrodes are provided between a plurality of dielectric layers, and external electrodes provided on opposite longitudinal end surfaces of the laminated body.
In general, the multilayer capacitor is electrically and physically connected to a circuit board by placing the external electrodes on mounting lands of the circuit board and joining the mounting lands and the external electrodes with a joining material such as solder (for example, see Japanese Unexamined Patent Application Publication No. 8-55752).
In such a multilayer capacitor, small mechanical distortion is sometimes caused by voltage application. When the distortion is transmitted to the circuit board, audible sound is emitted from the circuit board. To address this problem, the capacitor is sometimes mounted on the circuit board with another member being disposed therebetween (for example, see Japanese Unexamined Patent Application Publication Nos. 2004-134430 and 2010-123614). As the member to be interposed between the capacitor and the circuit board, for example, an interposer or a conductive support member is used.
An interposer is a substrate including an upper electrode to which the external electrodes of the multilayer capacitor are joined, a lower electrode to be joined to the mounting lands of the circuit board, and side electrodes provided on end surfaces of the interposer to connect the upper electrode and the lower electrode.
A conductive support member includes support legs to be joined at lower ends to the mounting lands of the circuit board, and the support legs clamp and support the multilayer capacitor in the air.
To mount a multilayer capacitor on a circuit board with an interposer being disposed therebetween, for example, a chip-component structure is placed on flux and a joining material applied on mounting lands of the circuit board, and the joining material is solidified. After mounting, flux residues remain around the joining material. Flux residues corrode peripheral electrodes, and cause rust. For this reason, it is necessary to clean off the flux residues after mounting. However, if flux residues remain between a portion between the circuit board and a substrate of the interposer, they are difficult to clean off sufficiently.